Experimental assessment of multiple contact wear using airborne noise under dry and lubricated conditions

Abstract

Generation of wear and airborne noise is inevitable in mechanical contacts of machine components. This paper addresses the effectiveness of airborne noise data in estimating the wear on a disc under multi-contact conditions. A pin on disc rig was employed to study the role of noise parameters on the evolution of the wear area. When a pin slides on the disc, the airborne noise is generated and subsequently a sound signal is obtained. These signals, for various sets of experiments, were recorded using a digital microphone. A Matlab code was developed and employed to estimate noise parameters from the recorded sound. Noise parameters including values of voltage RMS, noise counts and amplitudes of dominant frequencies were used to analyze the variation in the disc wear at different time intervals. These parameters were found to be effective in the determination of wear damage evaluation under different loads without lubrication.

Predictive Modeling of Surface Wear in Mechanical Contacts under Lubricated and Non-Lubricated Conditions

“…Authors have used the experimental rig as described in their recent work on noise and wear correlation [ 1 ]. In total, 37 experiments were performed on a pin on disc tribometer as shown in Figure 1 and considered for the statistical model development and validation.…”

“…The raw noise signals were acquired by an NI 9234 data acquisition module (National Instruments, Austin, TX, USA) in terms of sound pressure (units pascal) and sampling rate of 25.6 kHz. Images of the wear scars on the disc were taken from six different positions, the same as it was performed in the previous work, with a portable microscope (Dino-Lite AM413T, AnMo Electronics Corporation, Hsinchu, Taiwan) at a magnification of 200× as shown in Figure 2 [ 1 ].…”

“… Portable microscope used to capture images of the disc scar (Image reused under STM Guidelines. Content rights are owned by and permission requests for further reuse are handled by SAGE Publishing, CA, USA) [ 1 ]. …”

“…Mechanical structures and components generate airborne noise due to their contact mechanics even in normal operational conditions. The amplitude and the frequency of the noise have a direct relation with the surface wear of the contact zone [ 1 ]. As the material wears out due to contact, a rapid release of energy from localized sources within a material causes a noise to be generated, hence the two factors; noise and wear seem in relation with each other [ 2 ].…”

“…This has been established since the 1970s [ 6 ]. Studies indicate the effectiveness of analyzing contact based acoustic emissions in order to calculate the wear occurred in a component for various machine processes like sliding, cutting, milling, and tool manufacturing [ 1 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ]. The spectrum of the obtained acoustic emissions is further processed to measure count rates, RMS voltage, and also FFT analysis [ 10 , 13 ].…”